Browsing School of Chemistry by Issue Date
Now showing items 1-20 of 355
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Identifications and quantitative measurements of narcotics in solid mixtures using near-IR Raman spectroscopy and multivariate analysis
(1999)Raman spectroscopy offers the potential for the identification of illegal narcotics in seconds by inelastic scattering of light from molecular vibrations. In this study cocaine, heroin, and MDMA were analyzed using near-IR ... -
Identifications and quantitative measurements of narcotics in solid mixtures using near-IR Raman spectroscopy and multivariate analysis.
(ASTM International, 1999)Raman spectroscopy offers the potential for the identification of illegal narcotics in seconds by inelastic scattering of light from molecular vibrations. In this study cocaine, heroin, and MDMA were analyzed using near-IR ... -
Quantitative analysis of cocaine in solid mixtures using Raman spectroscopy and chemometric methods
(Wiley, 2000)Near-infrared (785 mn) excitation was used to obtain Raman spectra from a series of 33 solid mixtures containing cocaine, caffeine and glucose (9.8-80.6% by weight cocaine), which were then analysed using chemometric ... -
Quantitative analysis of cocaine in solid mixtures using Raman spectroscopy and chemometric methods
(Wiley, 2000-04-27)Near-infrared (785 mn) excitation was used to obtain Raman spectra from a series of 33 solid mixtures containing cocaine, caffeine and glucose (9.8-80.6% by weight cocaine), which were then analysed using chemometric ... -
Time-domain measurement of fluorescence lifetime variation with pH
(Society of Photo-optical Instrumentation Engineers, 2001)Advances in the design and miniaturization of the lasers and electronics required for Time Correlated Single Photon Counting (TCSPC) measurement of fluorescence lifetime have simplified the use of the time domain method. ... -
Classification of narcotics in solid mixtures using principal component analysis and Raman spectroscopy
(ASTM International, 2002-03-01)Eighty-five solid samples consisting of illegal narcotics diluted with several different materials were analyzed by near-infrared (785 nm excitation) Raman spectroscopy. Principal Component Analysis (PCA) was employed to ... -
Fluorescence lifetime based pH sensing using Resorufin
(2003)Accurate, non-contact pH sensing is of particular importance in the biological and clinical sciences. Fluorescence lifetime based pH sensing is potentially more useful than intensity based methods because of the reduced ... -
Influence of chemical composition on the fluorescence lifetimes of crude petroleum oils
(Society of Photo-optical Instrumentation Engineers, 2003)Fluorescence based methods are increasingly being used for the analysis of crude oils because they offer high speed, low cost, non-contact, and non-destructive testing options. The fluorescence of crude oils is due to the ... -
Evaluation of acridine in Nafion as a fluorescence-lifetime-based pH sensor
(2003)We report a novel fluorescence-lifetime-based pH sensing method that utilizes acridine incorporated into Nation (AcNaf) as the fluorescent indicator. The AcNaf sensor is excited using a 380 nm light emitting diode (LED) ... -
Machine learning methods for quantitative analysis of Raman spectroscopy data
(Society of Photo-optical Instrumentation Engineers (SPIE), 2003-08-27)The automated identification and quantification of illicit materials using Raman spectroscopy is of significant importance for law enforcement agencies. This paper explores the use of Machine Learning (ML) methods in ... -
Fluorescence emission from petroleum; a valuable information source for petroleum analysis.
(EniTecnologie, 2004)Despite the fact that most crude oils are dark coloured liquids, many are observed to be strongly fluorescent when illuminated with UV light. This fluorescence, which originates from the presence of aromatic compounds, is ... -
Time-resolved fluorescence microspectroscopy for characterizing crude oils in bulk and hydrocarbon bearing fluid inclusions.
(Ingenta, 2004)Time-resolved fluorescence data was collected from a series of 23 bulk crude petroleum oils and six microscopic hydrocarbon-bearing fluid inclusions (HCFI). The data was collected using a diode laser fluorescence lifetime ... -
Surface enhanced Raman scattering for narcotic detection and applications to chemical biology
(Elsevier, 2005)Raman spectroscopy is rapidly finding favour for applications in the life science because of the ease with which it can be used to extract significant data from tissue and cells. However, the Raman effect is an inherently ... -
Analysis of hydrocarbon bearing fluid inclusions HCFI) using time-resolved fluorescence spectroscopy
(Society of Photo-optical Instrumentation Engineers, 2005)Hydrocarbon-bearing fluid inclusions (HCFI) are microscopic cavities within rocks that are filled with petroleum oil, the composition of which may not have changed since the trapping event. Thus, the composition of that ... -
Analysis of crude petroleum oils using fluorescence spectroscopy.
(Springer, 2005)Crude oil is defined as a mixture of hydrocarbons that existed in the liquid phase in natural underground reservoirs and remains liquid at atmospheric pressure after passing through surface separating facilities (joint ... -
Monte Carlo simulations of liquid crystals near rough walls
(American Institute of Physics, 2005-02-15)The effect of surface roughness on the structure of liquid crystalline fluids near solid substrates is studied by Monte Carlo simulations. The liquid crystal is modeled as a fluid of soft ellipsoidal molecules and the ... -
A discrete P⋅⋅⋅I I⋅⋅⋅P assembly: the large influence of weak interactions on the 31P NMR Spectra of Phosphane–Diiodine Complexes
(Wiley, 2006-02-06)Seeing I to I: The reaction of a weakly coordinating carboranyl phosphane ligand with I2 leads to the formation of an adduct containing the bridging P⋅⋅⋅I[BOND]I⋅⋅⋅P assembly in the solid state (see picture; I purple, P ... -
Comparison of the fluorescence behavior of a biocrude oil and crude petroleum oils
(ACS Publications (American Chemical Society), 2006-02-15)The production and characterization of biocrude and petroleum like products from natural, renewable resources such as oil-bearing plant seeds is an interesting area of research at the moment. The present article discusses ... -
Structure of molecular liquids: cavity and bridge functions of the hard spheroid fluid
(American Physical Society, 2006-06-28)We present methodologies for calculating the direct correlation function c(1,2), the cavity function y(1,2), and the bridge function b(1,2), for molecular liquids, from Monte Carlo simulations. As an example we present ... -
Prediction of pK(a) values of nido-carboranes by density functional theory methods
(American Chemical Society, 2006-08-25)A great parallel exists between metal complexes of cyclopentadienyl and arene ligands on one side and metal complexes of the nido derivatives of the icosahedral o-carborane clusters. With few exceptions, the metal complexation ...